| 摘要 |
PURPOSE:To produce the title foam having finer cells and improved-uniformity while preventing the resin from building up at the tip, slit of an extrusion die by mixing a PS resin with a specified gellike mixture and extrusion-foaming the resulting mixture. CONSTITUTION:20-40% particles such as silica or alumina particles of a particle diameter of 0.5-20mum are uniformly dispersed in water in the presence of optionally a surfactant to obtain a suspension. This suspension is mixed with 3-10 wt.% highly water-absorptive resin (e.g. crosslinked polyacrylic acid) of a particle diameter of 100mesh or below to obtain a gellike mixture. A PS resin is mixed with 5-20 wt.%, based on the resin, gellike mixture and optionally azodicarbonamide, and the resulting mixture is extrusion-foamed. |
